Centrifugal mold and liner



Feb. 27, 1951 E. R. oLsl-:N ET AL CENTRIFUGAL MOLD AND LINER Filed Jan. 9, 1950 Patented Feb. 27, 1951 aman oristano-ast More LINEE Ernest. Re Qlson, Grand Ha Flora and-Glifordlh Lon and. Eydolph, `usliegon, Mich.,

assignors to Hastings lfaii1iifmaturing"l Go1n`4 pany', Hastings, Mich. A

@glio/ation, Jarrett 9 19.541,., SloriolflfoY 13.71506y This invention relates improvements cen; tr-ifugal mold'` and liner.

This application is a continuationA inl part or our application for Letters Patent,1 Serialil No. 711104,44@ -led November 1-8', 1'946, now Patent No, 2,495,811; issued January 3117-, 1950;

The main objects of this invention are;

First, to provide a permanent centrifugal-mold and a vliner therefor presenting ay continuous substantially smooth surface against which the metal is cast,

Second, to provide aV centrifugal mold and liner in which the liner` is a preformeclfV asbestos or other heat resisting sheet which may be quickly and Conveniently inserted and @ots to provide, a. continuous liner for the `mold Wall.

Objects relating to details and economies or the invention will appearv` from the description to fol-low, The invention is pointed out in the claims.

A preferred' embodiment of the invention is illustrated.- in the accompanying drawings, in which:

Fig. 1 is a fragmentary side elevational` viewpartiall-y in longitudinal section or a centrifugal mold embodying our invention.

Fig. 2; is an enlarged'` fragmentary perspective viewof the moldsectioned onl a lineH corresponde ing to line 22- of Fig-. 1f.

Fig; 3- is an enlarged fragmentary transverse section illustrating detailsA ofthel arrangement ot the liner in relation to the mold wall. l

Eig; 4 is a feragmentarv` sectional View corresponding to. that of Fig; 3 ot a modifiedforrn or embodiment oir our invention.

@or present invention is an adaptation or and in some respects an improvement upon the invention disclosed in our Patent No. 2,489,280, issued NovemberA 29, l949 Our present invention provides for a liner-completely covering. the mold: cavi-ty wall and at the same time permitting expansion ofthe liner into eiecti-ve supported relation to the. moldv wall and permitting. it to oonform to the expansion of:V the mold wall such as mayV result from casting heat and the. removal of the liner with the casting.

In the drawing the mold wall II is shown as generallycylindrical and its inner endwall 2 is carried bythe shaft or spindle 3L. The outer annular end plate 4- provides a central opening 5. This end plate is commonlyhingedorother-` wise rer-no-vablyl supported, the, details not being illustrated as they form no part ofourA present invention.

The inner surface of the mold; cavity wall is mondo@- Wtkl. e. voototiog. moons. that illustrato@ orologio the. forro of longitudinal grooves o-whoh. grooves are. of. Sooo Width that when the, Hoor l. is disposed Within tho, mold it extends, ooross.. the grooves, but doos. not enter, into the, Semo. The dimensions. ofthe. grooves Gr as illus# trotod; are, Somewhat exaggerated lo proportion to. tho Wollt thi'olsoess orlo diameter.. The orio: ploto- 4 is provided, with. op annular grooves. on its inner side communicating with the ventilata ing grooves G when the end plate is in position, The groove 8y has vents 9 opening toV thel outer side ot the plate. ln addition to the Ventilating grooves 6; the mold Wall has a relatively Wide, shallow,V longitudinally extending liner edge receiving groove Hl .extending VfromV end to end thereof, v

The pretormedsheet liner 1 is of heat resisting material desirably of' sheet'asbestos and is bend-` able so that it may be formed into a roll;` and inserted longitudinally into the mold cavity. The dimensions of the liner exceed somewhat the internal circumferentialdi'aI-neter of` the mold Wall so that the edgesy of@ the liner overlap when the liner` is expanded into supported relationv to the mold wall. @ne edge portion H ot the liner or substantial Widtn is disposed in the liner receiving groove I-Uj, the linerbeing suciently exi'ble so that when the liner is ysubjected to the Weight of? the metal resulting from the centrilugalfaction ofn the mold, the portion Ilv ott'- sets at -2- and is-suppor-ted by the bottom of-l the groove. rlheV otheredge portion, designated L3, of; the, liner laps upon the inne-r side of the portion M,y the linerbeing ov such width that its edge |41 is closely adjacent to the offset I-2. The edge l5 of the liner vdesirably abuts the edge I6 of the groove to aid the correct positioning ofthe liner Within the mold.

The lapping por-tions of the liner are not connected so that Hthe liner is free to expand into supported relation with the mold wall even though the mold Wall may expand when it becomesl heated as a result ofl` casting oper-ations.

'I'jhis insures a complete fitting support off thel liner with the mold wall and the metal will not flow behind the liner This lapping of the liner avoids any chill line, that is, the whole surface of the mold is covered- Desirably a Ventilating groove HV is provided at the bottom of the liner receiving` groove l0.

The heat resistant material, such as asbestos, for example, is commonly formed into a sheet with a binder,I` oommonlyo starch or the like. This binder is consumedby the heat and the 3 ventilation of the mold wall permits the escape of the products of combustion. The Ventilating groove Il is desirable as there is a double thickness of the liner at the overlap and therefore it is desirable that the products of combustion escape.

In the modification shown in Fig. 4 one edge of the groove or recess i8 merges into the mold wall with curved lines, thus eliminating an ofi:- set of the liner as at l2. The edge I of the liner is abutted against the edge i9 of the recess while the inner edge portion of the liner laps upon the portion disposed within the recess.

With this structure and arrangement of parts the liner formed of sheet asbestos may be quickly and easily inserted and accurately positioned. Desirably the liner has sufficient resilience so that it is merely necessary to roll the liner up in a cylindrical form of less diameter than the mold and insert it so that the edge I6 thereof engages the edge of the groove and the liner is then released and allowed to expand within the mold in supported relation with the walls of themold. If it does not closely contact the walls of the mold when thus inserted it will expand into supported contact therewith when the metal is poured and as the liner` is subjected to the centrifugal thrust thereof. The liner prevents undesirable chill and eliminates the necessity for heat treatment before machining. Also the castings may be made quite close to size and thereby minimizing machining.

We have illustrated and described highly practical embodiments or adaptations as we believe this disclosure will enable those skilled in the art to embody or adapt our invention as may be desired.

Having thus described our invention, what we claim as new and desire to secure by Letters Patent is:

1. A casting apparatus comprising a permanent centrifugal mold having longitudinally extending Ventilating grooves in its inner surface and a longitudinal liner receiving groove of substantially greater width than depth, a nonmetallic bendable preformed sheet liner of heat resisting material positioned in said mold in supported facing relation with the wall thereof and across said Ventilating grooves therein, one longitudinal edge portion of the liner being disposed in Said liner receiving groove in outwardlyoifset supported relation tothe bottom thereof, the other edge portion of the liner` being disposed in side overlapping relation to a portion of the liner disposed in the groove the overlapping edge being closely adjacent to the offset, the depth of the liner receiving groove being approximately equal to the thickness of the liner.

2. A casting apparatus comprising a permanent centrifugal mold having longitudinally extending ventilating grooves in its inner surface and a longitudinal liner receiving groove of substantially greater width than depth, a nomnetallic bendable preformed sheet liner of heat resisting material positioned in said mold in supported facing relation with the wall thereof and across said Ventilating grooves therein, one longitudinal edge portion of the liner being disposed in said liner receiving groove in outwardly offset supported relation to the bottom thereof, the other edge portion of the liner being ldisposed in side overlapping relation to a portion of the liner disposed in the groove the overlapping edge being closely adjacent to the offset.

3. A casting apparatus( comprising a perma- 4 nent centrifugal mold having longitudinally extending ventilating grooves in its inner surface and a longitudinal liner receiving groove of substantially greater width than depth, a nonmetallic bendable preformed sheet liner of heat resisting material positioned in said mold in supported facing relation with the wall thereof and across said Ventilating grooves therein, one longitudinal edge portion of the liner being disposed in said liner receiving groove in outwardly offset supported relation to the bottom thereof, the other edge portion of the liner being disposed in side overlapping relation to a portion of the liner disposed in the groove the overlapping edge being closely adjacent to the offset, there being a relatively narrow Ventilating groove in the bottom of said liner receiving groove and across which the edge portion of the liner disposed in the liner receiving groove extends.

4. A casting apparatus comprising a permanent centrifugal mold having a generally cylindrical mold cavity wall surface and a liner receiving groove of substantial width extending longitudinally thereof, and a nonmetallic longitudinally split preformed bendable sheet liner of heat resisting material positioned in said mold cavity in supported facing relation to the wall thereof, one edge portion of the liner being positioned in the liner receiving groove in supported relation to the bottom thereof, the other edge portion of the liner being disposed in overlapping relation to the inner side of the edge portion of the liner disposed in the groove but being unconnected therewith permitting expansive movement of the liner, the groove being of a depth substantially equal to the thickness of the liner.

5. A casting apparatus comprising a permanent centrifugal mold having a generally cylindrical mold cavity wall surface and a liner receiving groove of substantial width extending longitudinally thereof, and a nonmetallic longitudinally split preformed bendable sheet liner of heat resisting material positioned in said mold cavity in supported facing relation to the wall thereof, one edge portion of the liner being positioned in the liner receiving groove, the other edge portion of the liner being disposed in overlapping relation to the inner side of the edge portion of the liner disposed in the groove but being unconnected therewith permitting expansive movement of the liner.

6. A casting apparatus comprising a permanent centrifugal mold having a longitudinally extending recess in its mold surface and a nonmetallic liner of sheet heat resisting material disposed in the mold in supported relation to the mold cavity wall, one edge of the liner being positioned in said recess, the other edge of the liner being disposed in lappingrrelation to the edge portion of the liner disposed in the recess butbeing unconnected therewith permitting free expansion of the liner into contacting supported relation to themold surface, A

7. A casting.apparatuscomprising a mold cavity wall having a longitudinal inwardly facing recess therein, and a nonmetallic preformed bendable sheet liner of heat resisting material disposed within the mold cavity in supported relation to the wall thereof with one edge of the liner disposed in said recess, the other edge of the liner being disposed in overlapping relation to the edge disposed in the recess but being free therefrom.

LA castingapparatus comprising a mold cavity wall having a longitudinal inwardly facing recess therein extending from end to end thereof, and a nonrnetallic bendable preformed sheet t REFERENCES CTED The following references are of record in the iile of this patent:

Number x N 2,494,405 1U UNITED STATES PATENTS Name Date Grasser Nov. 6, 1900 Shields June 14, 1910 Olsen Jan. 10, 1945 

